A chain of custody form is a document that tracks the sample through
all procedures and changes of analyst during the collection and analysis

How can alcohol be tested for?

There are a number of ways that alcohol (ethanol) can be tested for.
Breath alcohol can be tested for using a breathalyser. Blood alcohol can
be measured, as well as urine alcohol. There are other biomarkers available
to monitor alcohol/ethanol consumption, such as plasma CDT levels and
urine ethyl glucuronide levels.

How long can drugs be detected for after they have been taken?

The detection window can vary for different drug classes. As a general
rule of thumb, drugs are detectable for 2-3 days following intake. There
are obviously some drug classes that remain for longer periods of time
(i.e. cannabinoids) and some that are detectable for shorter periods of
time (i.e. gamma-hydroxybutyrate).

Can I ask for my sample to be retested?

Yes, you can ask for your sample to be re-tested. Under the Australian/New
Zealand standard for workplace drug testing, samples are required to be
retained for three months post testing.

Can my doctors’ prescription cause a false positive result?

Yes, some prescription drugs do react with the analyses we use. When
filling out the chain of custody documentation, always write down all
medication (both prescription and over-the-counter) being taken or having
been taken in the previous week.

Will my potential employer know what medications I am on?

No, your employer will not know what medications you are on unless they
are one of the drug classes being tested for and you return a positive
result for your urine sample.

If my screening test is non-negative and my confirmatory test
is negative what happens?

If your confirmatory test does not confirm the presence of the drug
class indicated from the initial screening test then the report states
that drugs were not detected.

Why is my original sample split into two or three?

The original sample is split to allow analysis of one of the samples
while the second sample is held as a reference sample, available for analysis
by an independent testing laboratory should there be a dispute over the
initial testing.

What happens to the B sample?

The sealed ‘B’ sample is stored frozen at -20°C for
three months. Should a result be challenged, then this sealed sample is
available for analysis to confirm the original report.

Can I get a positive test result for cannabinoids from passive
inhalation?

No, the screening test cut-off value has been set to a level that excludes
the chance of detecting cannabis from passive exposure.

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